What happens if you put egg whites in lemon pie filling?

Adding egg whites to lemon pie filling is not traditionally done and may alter the texture and stability of the pie.

- Texture: Egg whites, when whipped, introduce air and create a fluffy texture. In a lemon pie filling, this could result in a foamier, less smooth consistency compared to using only egg yolks or whole eggs.

- Structure: Egg whites contribute to the structure and stability of baked goods through coagulation during baking. However, in a lemon pie filling that is not baked (like many traditional lemon meringue pies), the egg whites alone may not provide enough structure to hold the filling together firmly. The filling might become runny or loose.

- Taste and Flavour: Egg whites themselves don't have a significant impact on flavour, but they can affect the balance of tartness and sweetness in the lemon pie. The additional amount of protein from the egg whites could slightly alter the overall taste profile of the filling.

For these reasons, it's generally not recommended to add egg whites directly to lemon pie filling. If you're looking to achieve a specific texture or flavour, experimenting with alternative methods (such as incorporating meringue as a topping or using cornstarch as a thickening agent) may be more suitable.